A wheel mounted on a vehicle designed for running in a different environment from the earth, such as a planet and or natural satellite, is disclosed in Patent Document 1. In the wheel disclosed in this patent document, an inner ring to be connected to the axis of the vehicle and an outer ring to be brought into contact with the celestial body surface are connected with each other by spokes, wherein the outer ring and the spokes are each a rigid body. Thus, the wheel becomes elastically deformed to a negligible extent under load (i.e. compression force in the radial direction) from the vehicle. In such a wheel, it is less likely to have an adverse impact on the running performance when the wheel is used on a celestial body having a gravity not smaller than that of the earth and also a relatively hard surface.
Patent Document 1: JP 08-002204 A